The Beta Test Reaction
by Cassiopeia's
Summary: Penny had always been an impulsive person. So when after Leonard suggests the beta test Penny gives into a certain impulse she's been repressing for a long time things get complicated rather quickly. AU, set during and after 05x14 "The Beta Test Initiation"
1. Chapter 1

The Beta Test Reaction

 _AU, set during and after 05x14 "The Beta Test Initiation"_

 **-1-**

A beta test. Boy, Leonard Hofstadter sure knew how _not_ to turn on a woman. She rolled her eyes but it was in affection. She liked the little guy and after she had broken up with him a few years ago a part of her really regretted that.

Biting her lip she slowly walked over to sit on her couch. She had been beating herself up over her decision for so long and cursed herself countless times for being frightened. After all, Penny was a fighter, always had been. But during that time she had been young and just not ready for the seriousness of Leonard's feelings. She had felt pressured and like she was going to disappoint and hurt him in the end.

Of course, seeing him with Raj's sister had made her insanely sick, even though she had denied it tooth and nail. She had wanted him back so badly.

Now though, much later, she was on the verge of getting back with Leonard and suddenly she felt frightened again. Which was weird because it was the second chance she had wanted and Leonard's stupid beta test seemed to show that he was not going to pressure her the same way he had back then.

Her gaze fell on the couch table where one of Sheldon's latest science magazines was, the one she'd found in her mailbox yesterday and had yet to deliver it to the man in question.

Her whackadoodle of a neighbor was a whole other story. He was probably her closest friend and even though he had begun dating Amy he'd occasionally made sure to pay her extra visits which for him had to mean that he actually liked spending time with her, even though he sometimes claimed differently. After all, she was still his go-to-person when he felt bad, emotionally or physically, and to be honest, she loved those times with him, even if he sometimes drove her nuts. He'd done so right from the start and she knew he'd been equally infuriated but they had both worked hard to accommodate the other one in each other's lives.

With a smile, Penny remembered the first afternoon they'd met. In retrospect he'd been entirely clueless what to do with her, but that evening she'd been so fascinated by him. She'd seen his genius, even if she had not understood anything at all, and boy, had he been attractive. At least until the whole sitting in his spot thing. But even then, only a few minutes after meeting her, he had been trying to be nice to her which she knew by now was a pretty rare thing for him, considering he usually didn't care for people at all.

Then he'd broken into her apartment to clean it and while that had freaked her out big time, a tiny part of her had actually been a little flattered and over the years, she had often silently wondered if Sheldon, in his own clumsy, weird way, had been trying to flirt with her. These thoughts had resulted in her recalling her own attraction towards Sheldon, because objectively speaking, when he did not open his mouth, Sheldon Cooper was actually pretty handsome. He was tall, had the bluest eyes she'd ever seen, he was loyal and could be charmingly endearing if he wanted to be.

Penny had always been an impulsive person. Most of the time it turned out to be a weakness because it made her fall into all kind of messes which a more sensible, more collected person would easily avoid. She took a deep breath. The thought had been lingering at the back of her mind for five and a half years now and while she might be able to love Leonard one day she feared a part of her would always wonder.

She closed her eyes and mentally cursed herself because damn it, this was a really, really bad idea, but she had to know. It was probably the most selfish thing she would ever do because she knew both Amy and Leonard would be rightfully furious if they found out and how Sheldon would react, she didn't even want to know.

This really was a bad idea, she knew she shouldn't do this and yet, she found herself texting Sheldon to come over.

While she waited for his response with her palms sweaty and her heart pounding nervously, Penny tried to avoid thinking about the consequences which made her even more edgy.

And then there was suddenly Sheldon's triple knock, followed by him calling her name like he always did and she nervously let him finish his ritual before opening the door to face him.

His face was mostly blank but his blue eyes twinkled curiously as he looked at her. "Good evening, Penny. How may I assist you?"

She smiled at him but she knew it was strained. She could still not do this. She could still make up something stupid and have him leave in a mere matter of seconds without him ever questioning the incident because he wouldn't pick up on anything being weird. And it would be the right thing to do because he had a girlfriend, even if it was one weird relationship, and Leonard was his best friend and Amy was her own self-claimed bestie. Sheldon couldn't keep a secret and therefore there was no way he would not tell Amy and Leonard about this.

"Hey," she finally forced out, "how's it going, Sheldon?"

His eyebrow rose sharply and he eyed her disapprovingly. "Penny," he began in that tone of voice he always used on people when he was about the lecture them, "you're perfectly aware how I find idle chit-chat to be tremendously disdainful. Was there a specific reason why you asked me to come over?"

She let out a shaky breath and stepped aside. "Yeah, sorry. Come on in."

He gave her a nod and came inside. "Very well."

She closed the door behind him and was suddenly at a loss for how to proceed. It wasn't like she could sit down with him and just ask him because he would surely downright refuse her and probably ask her to see a doctor. On the other hand, she couldn't just grab him and kiss him either because it would surely scar him for life and she would have to explain to his mother what she'd done to her precious boy wonder.

"Penny? Are you alright?" He was suddenly standing right in front of her and looking at her with a surprising amount of concern on his handsome face which made Penny realize she must have been lost in her thoughts for a while.

"Uh, yeah, sure. I'm fine."

Sheldon frowned. "Penny, I must say, I'm beginning to concern myself over your wellbeing. At first you asked me to come over rather unannounced, at your door you greeted me in a way you very well know I do not appreciate and just now you seemed to be lost in your own thoughts. Are you in need for medical attention?"

She huffed and couldn't help but smile a little. "No, sweetie, I'm just a little…preoccupied."

He raised his eyebrow again. "With what?"

"We'll get to that," she quickly brushed off and took another breath.

By now, Sheldon was watching her like a hawk and she realized she had to treat very carefully now. "Hey, you trust me, right?"

He blinked, apparently surprised, but gave her a slow but firm nod. "While it is rather unexpected as you are of no comparable intellect to my own you have proven yourself over the course of the past five years to be there for me when I needed you and you stood up for me against a bully and on occasion even against our mutual friends. Therefore, yes, Penny, I do trust you."

She had to blink away her tears at that and smiled watery at him. "Just so you know, I trust you too, sweetie."

He gave her a confused look. "Of course you do. I am a trustworthy person."

Penny swallowed but tried not to show her nerves. "So therefore you also know that I would never do anything to intentionally hurt you or humiliate you where it matters, right?", she asked.

Sheldon frowned. "Well, as a matter of fact, I recall various incidents on which you bullied me."

Her smile froze and her eyes widened. "Sheldon, honey, I swear I was just teasing you. I promise. I'm sorry if-"

His frown deepened. "Are you currently affected by a deathly sickness?", he wondered, his head a little tilted and his blue eyes a little wider.

"What? No! Why would you say that?" Sometimes she really didn't understand him. Sheldon Cooper's track of thought was so far up over her head that it wasn't even funny. He was so smart, a beautiful mind genius, as she had once called him but it also caused him to be so different from any other person she'd ever met. Penny was sure he was probably one of a kind. Most people just didn't get him, not even Leonard or his other friends and they were the geekiest guys she knew.

"Well, you are currently expressing yourself like people do in movies if they know they are going to die. Also, it would explain youe confusing behavior tonight."

She rolled her eyes. "I'm not dying, Sheldon, alright?"

He nodded. "Very well."

"Alright, so you know you can trust me and that I would never hurt you or anything, right?"

"Well, we established the first part and I agree to the second part in moderation."

"Alright," she said, ignoring him, "so if I asked you to close your eyes and trust me you could do it because there was nothing to fear, right?"

He sharply blinked. "Excuse me?"

By now her nerves were making her voice shaky and her knees a little wobbly. Her palms were damp and she licked her lips nervously. "I promise I won't hurt you. Will you close your eyes and just stand very still?"

"Are you giving me a gift? Penny, I thought I explained in length why I hate gift-giving."

"Sheldon," she whined because why couldn't he for once in his life just shut the hell up and do as she asked?

He took a deep breath and his blue gaze met hers. There was definitely fear in there but also trust and it made her heart leap. "Very well, I will concede to this, but please, Penny, be aware my trust is hard to earn and easy to lose."

She rolled her eyes, unnerved by him because she was scared of doing this, scared of not doing this, terrified of her own reaction afterwards, out of her mind frightened of his and everybody else's and he was not helping. It wasn't like she could blame him because she wasn't exactly giving him any indications of what she was planning on doing and he must at least have the suspicion that whatever she was planning somehow included his person.

"Yeah, yeah," she said, "just close your eyes, honey."

And then he actually did, his tender eye lids gently fluttering until his eyes were closed. His expression was a little tense and his jaw line slightly clenched, making Penny realize how worried he was. Sheldon Cooper was a creature of habit, rules and control and closing his eyes, knowing someone else was going to do something unknown to him or with him had to be very difficult for him.

Penny bit her lip as she slowly came closer, watching him attentively. His lips were thin but slightly pink, his cheeks soft with just the barest hint of a stubble. She remembered their first hug years ago on Christmas when he had clumsily but entirely taken by gratitude had embraced her out of his free will. In his shaky movement his cheek had accidentally brushed against hers, all down her neck and it had made her hairs stand up and her insides tighten.

She stepped closer and was now near enough to feel the warmth of his body and sniff his unique, clean smell. Sheldon stood ramrock stiff upon realizing Penny was so close that their bodies were even slightly touching.

"Penny," he said, his voice sounding vulnerable and warning at the same time and she noticed how his jaw clenched tighter. His eyes moved hectically behind his lids.

"Remember what I promised," she said, trying to calm him, but her own voice, caused by her nerves and her rapidly beating heart, came out like a whisper.

He didn't give a response to that and instead tilted his head a little, as if trying to figure out her next movement. She doubted he would because kissing wasn't a direction Sheldon's mind ever went into.

Penny's heart raced as she shakily raised her arms to his shoulders. The moment they found them, Sheldon jumped up but Penny could quickly tighten her grip on him.

"What are you doing?", inquired, his voice trembling and when she looked up to his face she realized he had opened his blue eyes. The look in them was intense and not anything she had ever seen before. Maybe it had to do with the fact that they were so close that they were practically breathing the same air and the many emotions in his blue orbs made her breath catch and freeze this moment in time. She still wondered how anybody could say Sheldon didn't have feelings because she could see them all in his eyes.

"I…I'm…I I just…," she trailed off, not knowing how to explain and the way his gaze was captivating hers made it hard to think and even harder to speak coherently. She knew exactly what she wanted and yet, staring up into his eyes she could not find it in herself to bridge the last gap between them. Her heart was pounding so hard in her chest she kind of expected it to jump out into Sheldon's arms any second now.

"Please, sweetie," she whispered and for once Sheldon seemed to understand because he slowly closed his eyes again.

The next few seconds happened in somewhat of a haze. She slowly inched closer and in hindsight he must have realized her intention at some point but he kept still anyway. When her lips finally touched his it wasn't anything like she had imagined it to be. For years she had mostly not thought about it at all, or rather she hadn't allowed herself to think about it because he was Sheldon and she was Penny and there were countless reasons why they would never happen. Yet, mostly at night after a day when he had done something sweet or really, really annoying she had indulged herself in the fantasy. On her more romantic days she had imagined fireworks and them both instantly realizing they were ridiculously in love with each other which was rather stupid. Sometimes she imagined simply grabbing him in midst of a fight and just kiss him senseless.

However, when it finally happened it was a little bit of all those scenarios and none of them at the same time. It was toe curling and her heart beat like crazy. Her hands were still clutching his shoulders and she could feel his heart thundering against her chest because they were so close. With one last press, she finally pulled away, far enough to meet his eyes nervously. She had no idea what his reaction was going to be like because while kissing him had felt intensely good (which was rather worrying, considering she was supposed to be beta dating his best friend) but Sheldon had not exactly participated. Not that she had expected him to because that she knew he'd probably had no idea how, even if he had wanted to which she doubted.

For a second, Sheldon's eyes remained closed and when he opened them, the expression on his face took her breath away again. There was of course a bit of irritation and even fear but also wonder and a kind of light she had never seen in him.

"I...why did you do that?" His voice sounded the tiniest bit raspy which sent a pleasant quiver down her spine.

Curiously Penny realized he had yet to dash for the bathroom to disinfect his mouth. "I…kind of have been wanting to do that for years," she admitted honestly.

He frowned down at her in confusion. "Why?"

The incomprehension on his face and in his tone of voice made her smile. And there it is, she thought, because had she actually been expected him to just get what she was talking about? While a part of her had always wished he had actually been flirting with her, she consciously knew that could not be the case because Sheldon didn't do flirting or anything remotely close to that.

She let out a breath while noticing they were still pretty close. It was kind of amazing because while he wasn't exactly leaping up in joy because she had kissed him he also wasn't running back to Texas.

"Why are you smiling?", he asked.

"I did it because you're pretty handsome as long as you keep your mouth mostly shut and you are my friend and I like you a lot and I just really, really wanted to do that," she replied, ignoring his last question.

In response, Sheldon raised his eyebrows and studied her attentively. Inexplicably, it made her blush and she had probably not blushed around a guy for quite some time.

"And what did you conclude?"

Now it was her turn to frown. "What?", she inquired, having no idea what he was talking about.

He gave her that disapproving look again he always send her way when he wasn't happy with her. "Penny, you told me you have been wanting to kiss me for a while. Every action we carry out has always been calculated, either consciously or subconsciously. Therefore I can assume you imagined the incident previously and assessed it accordingly."

Slowly understanding what he was asking, Penny had to bite her lower lip in order not to smirk. As previously stated, Sheldon Cooper definitively wasn't a regular guy and therefore, him kind of asking if he'd been any good was rather funny. Then, upon thinking further, she realized that wasn't what he was asking.

"It was tingling and toe curling," she stated softly.

He watched her like a hawk. "And that is a positive outcome?"

She nodded. "Yeah. If you feel that in kiss that isn't even a real one because only one partner is actually active that's a pretty strong sign the two are a great match."

He frowned, probably upon her grammar, but Penny ignored him.

"I know I probably freaked you out with it and I also know it was a selfish thing to do because first and foremost I should have asked you first and then there's-"

She was cut off by Sheldon leaning forward and pressing his lips to hers for the second time. Her eyes instantly closed as her stomach dropped and this was probably the most surprising and yet most intense kiss of her life. Without any thought her arms came up to wrap around his neck and then she felt hesitant long fingers slowly, oh so gently coming to rest on her waist.

Holy crap on a cracker, Sheldon and she were kissing and hot damn it, it felt hot and amazing and she didn't ever want him to let go of her again.

Barely able to stop herself from swiping her tongue across his soft lips, Penny gently reached her fingers up into his hair and suddenly, Sheldon let out a sound that sounded so much like a moan that her nipples tightened in response. He apparently noticed because he pulled away a little abruptly, his hair a mess, his lips a darker shade of red and his cheeks rosy.

His blue eyes were more of a marine blue now and his pupils were slightly dilated, she noticed happily surprised, as he focused intensely on her.

"I had not imagined osculation to feel like this," he finally said quietly, his voice a little rough and Penny's heart was beating so hard it was almost painful. Was he actually admitting he _liked_ kissing her? Because what would that mean? For them and for Leonard and Amy and everything in between the four of them? How would she feel if – no, he couldn't actually be thinking about this, could he?

"Like what?", she whispered, desperate to hear his answer and terrified of it at the same time.

He opened his mouth a few times and Penny realized Sheldon Cooper actually seemed to be at a loss for words for once. And then he quickly turned around and fled.


	2. Chapter 2

**Hey there, thanks a lot for your reviews and messages. Here's the second part of this little thing. I hope you enjoy it.**

* * *

 **-2-**

No one had seen Sheldon in days. Penny only knew that because she had received an annoyed call from Amy, telling her that Sheldon was ignoring her. Penny's stomach had dropped rather fast because she knew exactly what was going on with him. After all, she had been the stupid bitch who had made a move on her bestie's boyfriend and her own kind-of-boyfriend's best buddy. It had been a move she thought she wouldn't ever pull and yet, somehow her deepest, darkest thoughts had finally caught up with her.

Kissing Sheldon had been a fantasy of hers she'd been pushing into the far end of her mind for so long and a part of her had apparently been unable to resist anymore. The crazy thing was that Sheldon had kissed her back. Of course not instantly but the second, a lot more passionate kiss had been initiated by him which was a pretty big deal, considering he had never kissed anyone voluntarily before and that he usually claimed that he was above anything physical that even remotely reminded of intimacy. It had been so hot and toe-curling and exactly like she had both hoped and feared it would be. Apparently she had more chemistry with Sheldon than she had ever had with anybody else, including Leonard whom she had been thinking she might be able to fall in love with over time. For days, next to her guilt and panic, only once question constantly ran through her head: had it been a fluke, a spur of the moment thing or would it feel like that again if they kissed again. Of course the more sensible part of her brain reminded her that it would definitely be a slutty, bad move to kiss Sheldon again, if he agreed and even more so if he didn't and she would just spring it on him like she'd done a few days ago. The other part though, the one that kept her awake at night and left her wondering what her whackadoodle of a neighbor looked like naked and panting above her, his blue eyes dark with lust and his skin sweaty as he moved deliciously with her, that part wanted her to do it again. Desperately.

The problem was that no matter if she won or lost the fight against her own little devil, it wouldn't change what had happened prior. She and Sheldon had kissed which made it cheating at least on Amy and kind of on Leonard too, even if they were not really dating yet again.

Therefore, she had also been hiding which was probably why she hadn't known Sheldon had not been seen for three days before Amy called her. She had been too guilty and shocked of how good it had felt to kiss Sheldon to face Leonard or even worse her whackadoodle himself. Of course Leonard had been pestering her, trying to get her to answer if she was onboard with the whole beta test thingy, but she'd avoid him each and every time, not answering her door and texting him she had to work long.

When Amy had called her Penny had found out that Sheldon had apparently took the bus to work very early and left long after Leonard had gone home. He did not eat with the guys during lunch break but instead stayed hidden in his office. The guys and Amy thought he was in a mood caused by some science problem but Penny knew better. Not that she had informed Amy of that but she knew exactly why Sheldon felt the need to hide. Because she had seen the look on his face, had felt what he'd felt while they had kissed passionately in her apartment. He had certainly not acted like someone who hated physical intimacy. Naturally, he had been frightened by his own reaction and had fled but that didn't mean it had not happened.

The only question left now was where did that leave Leonard, Amy, Sheldon, her and the different relationships they had with each other?

With a sigh, Penny finally grabbed her dirty laundry and moved to open the door. For the past few days she hadn't exactly been in the mood to do chores but now there weren't any more panties left in her closet so she figures she couldn't prolong washing her clothes any longer. Most of the time she still did in on Saturdays evenings with Sheldon but today she was intensely happy she wasn't a creature of habit like Sheldon who wouldn't be able to vary from his routine.

Quickly grabbing her keys, she went out into the hallway only to be stopped by Leonard who'd pulled his apartment door open like a maniac and almost jumped out into her path.

"Penny! Hey!", he said urgently as her stomach dropped almost painfully.

Damn it, damn it, damn it. Shouldn't he be still at work or something? Penny definitively didn't feel up to talking to him yet.

"Hey Leonard," she greeted, a false smile on her face. Her heart squeezed painfully in her chest and she had to swallow against the lump in her throat. "I'm…uh…a little busy," she said, quickly moving the basket of dirty laundry in her arms.

"Yeah, I just…feel like I haven't seen you in days," he replied, sounding a little depressed.

Penny grimaced. Yeah, he hadn't had he? But what else had she been supposed to do besides staying away? She'd made out with his best friend after all.

"I…uh…have been busy," she added lamely, biting her lip and hoping to god Leonard would back off and let her go down into the laundry room.

"Yeah, I know," Leonard said, fidgeting slightly from one foot to the other. "I just…" He eyed her hesitantly, biting his lower lip. "Have you…maybe…been avoiding me?"

Her stomach dropped all over again and of course she blanched and automatically went into defensive mode, even though she knew he was right. "What? No! I haven't," Penny denied but Leonard seemed to see right through her.

He took a few steps closer until he was near enough to take the basket away from her and put it on the floor. Penny desperately wanted to step away but forced herself to stay put and swallowed against the lump in her throat.

"Look, Penny, I'm not pressuring you and I meant what I said about the beta test. We can take all the time you need and-"

And suddenly the words stumbled right out of her mouth, turning their whole universe upside down. Letting the bomb detonate. "Leonard, there's someone else."

Her own eyes widened upon realizing she had spoken out loud what she hadn't even admitted to herself yet because she couldn't actually consider Sheldon as boyfriend material, could she?

Of course, kissing him had felt like the single most erotic thing in the world and he could be considered to be her best friend because while he could be a pain in the ass he was also loyal, honest, always had her back and he could be charmingly endearing if he wanted to. But Penny also knew how he was with Amy and – oh god, Amy!

What the hell was she doing thinking these thoughts, especially while Leonard was standing right in front of her, looking all kinds of brokenhearted and she couldn't believe herself because a week ago she had been really looking forward to get back together with Leonard again. How could two kisses, with Sheldon Cooper of all people, make her throw away everything she'd hoped for for so long?

"Leonard," she tried, moving forward to grab his hand but Leonard moved away as if she'd just electrocuted him. A wounded look of betrayal all over his face.

"Why? How? I…I mean…I thought…", he stuttered and because of all the pain on his kicked puppy dog face, tears started pooling down her cheeks.

"I'm so sorry," she whispered brokenly, her voice full of pain, sadness and confusion.

"Have you been seeing him all these past few days?", Leonard asked, causing her eyes to widen again upon the sentiment. Into his pain was slowly moving a shade of anger.

"No, no, no!", Penny quickly clarified, "it's not like that," but Leonard was shaking his head in disbelief, like he hadn't even heard her.

"How could you do this to me? How?"

And then, before she could say anything else, before Penny could try to make amends, Leonard had already turned around and slammed the door of 4A shut behind himself.

Crap, what in god's name had she done?


End file.
